Many different types of radio receivers are available. Conventionally, receivers were formed of various discrete components and implemented within a desired type of solution such as a desktop radio in the form of a clock radio, an integrated radio within a stereo receiver, a portable receiver such as a handheld receiver, or a mobile receiver such as incorporated in a car stereo.
As technology has advanced, radio receivers have begun to be implemented within semiconductor integrated circuits. In this way, much smaller radio solutions are possible to enable implementation of radios within smaller devices such as MP3 players, cellular telephones such as smart phones and so forth. In addition, semiconductor advances can provide improved audio quality by way of signal processing techniques.
One issue with regard to radio signals can be the presence of impulse noise. Impulse noise can occur due to various sources of interference within a radio frequency (RF) signal or a downconverted frequency to which an RF signal is converted. To remove impulse noise, an impulse blanker can be provided in a radio receiver. Different types of blankers use different mechanisms to remove impulse noise. However, in the presence of a close-in blocking signal such as an adjacent radio channel, impulse noise can distort the desired audio signal. Due to the presence of a close-in blocker, known impulse blankers do not operate well and accordingly are either turned off, or if allowed to continue to operate, can cause much distortion of the audio signal.